1. Field of the Invention
This invention relates to a system for indicating the oil level in the oil pan of an internal combustion engine and adding a predetermined quantity of oil thereto when necessary.
2. Description of Related Art
It is well-known that if the oil level in the oil pan of an internal combustion engine drops below a prescribed level irreparable harm will be done to the internal components of the engine. Accordingly, modern automobiles are equipped with an oil pressure gauge to indicate a lack of adequate pressurized oil circulation within the engine. However, by the time the oil pressure gauge, generally nothing more than a light bulb, indicates that the oil pressure has dropped, there is little or nothing that can be done about it. The automobile must be stopped immediately and an additional source of oil must be sought. All too often the operator of the vehicle attempts to continue travelling with inadequate oil pressure thus injuring his vehicle. Inasmuch as modern automobiles are equipped with such pressure sensors, it is incumbent upon the vehicle operator to maintain a supply of oil or have his oil checked through the use of a dip stick at regular intervals. However, most modern drivers are not prone to take such measures and therefore some device which can aid in the avoidance of engine damage due to lack of oil is necessary.
Several systems for maintaining the proper level of oil within an engine have been proposed. U.S. Pat. No. 2,564,231, issued Aug. 14, 1951, to Pitney, shows a liquid level maintainer which includes an airtight auxiliary oil reservoir disposed above the engine and a tube extending from the reservoir to a predetermined height in the engine oil pan. When the oil in the oil pan falls below the tube, air enters the reservoir and oil from the auxiliary reservoir is allowed to enter the oil pan. U.S. Pat. No. 2,615,442, issued Oct. 28, 1952, to Berry, shows an oil maintaining apparatus wherein a float is disposed in the engine crankcase for indicating the level of oil therein. The feeding of oil from a reservoir to the crankcase is produced by vacuum of suction from the intake manifold. U.S. Pat. No. 3,282,380, issued Nov. 1, 1966, to Burrell et al shows an automobile oil changer wherein a reversible pump is connected in a line which extends from the drain opening of an engine crankcase to a container located above the engine. The pump is operated in a first direction for removing oil from the engine and depositing it in the container. The container can be filled with fresh oil and the pump operated in a second direction for refilling the engine. U.S. Pat. No. 3,447,636, issued June 3, 1969, to Bonfilio, shows an automatic oil exchanging system having a first container for receiving the used oil from the engine crankcase and a second container for storing a fresh oil supply to be dispensed to the crankcase. The system automatically removes engine oil to the first container and, when this is accomplished, replaces it with a fresh oil from the second container. U.S. Pat. No. 4,091,895, issued May 30, 1978, to Lang, shows an oil level sensing and replenishing apparatus comprising a standpipe type sensing apparatus which allows venting of an auxiliary oil reservoir to provide gravity induced fluid flow from the reservoir to the crankcase when the level of the crankcase is below a predetermined minimum.